public class Demo {
    public static void main(String[] args) {
        String s1 = "abc" + "def";
        String s2 = new String(s1);
        if(s1.equals(s2)){
            System.out.println(".equlas succeeded");
        }
        if(s1 == s2){
            System.out.println("== succeeded");
        }
    }



}
